Electric brake.



- Patented 001.29, I901. P. P. CRAFTS.

ELECTRIC BRAKE.

(Applies-H05 filed Nov. 30, 1900.

4 Sheets-Sheet 2.

(No Model.)

T m n lil l l INVENTUR H I ha \WO 2W H w w lli H 4 m, m m I N WITNEEEJEE v if 24.4w

UNITED STATES PATENT OFFICE.

PERLEY P. CRAFTS, OF BOSTON, MASSACHUSETTS, ASSIGNOR THE AL- GONQUIN ELECTRIC BRAKE COMPANY, OF BOSTON, MASSACHUSETTS, A

CORPORATION OF MAINE.-

ELECTRIC BRAKE.

SPECIFICATION forming part of Letters Patent No. 685,393, dated October 29, 1901.

Application filed November 30,1900. Serial No. 38,136. (No model.)

To to whom it may concern:

' Be it. known that I, PERLEY P. CRAFTS, a

citizen of the United States, residing at Boston, county of Suffolk, and State of Massachusetts, have invented certain new and use- D, which are keyed to the axle, so as to r0- tate therewith, but capable of sliding longitudinally thereon, and I surround the drum B with a coil, which. when energized will attract the brake-disks D D, and so produce a ful Improvements in Electric Brakes,of which the following is a specification, reference being made to the accompanying drawings, wherein--- Figure 1 is adiagrammatic plan of a doubletruck car having my invention applied thereto. Fig. 2 isa diagram of the circuit connection. Fig. 3 is a side elevation of a car-axle with my improved magnetic clutch and lock applied thereto. Fig. 4 is a vertical section "of Fig. 3, and Fig. 5 is a transverse section through the line 4 4 of Fig. 3.

My invention relates to that type of electric brake which is operated by the line-cur- 2o rent supplied to an electrically-propelled vehicle and in which there is a regulated main magnet which serves to apply the brake, while the brake is locked mechanically and automatically bya spring, but unlocked at 2 5 will by a second unlocking-magnet, preferably in a shunt-circuit parallel to the circuit of the main magnet. The brake is also of the type wherein the main magnet serves to put a winding-drum into magnetic or frictional 3o engagement with a rotating axle, so as to be turned thereby,while a chain connected to the brake-levers is wound upon the said drum.

Referring to Fig. 1, A represents the ordinary central brake-lever of a well-known type of brake, while rods A and A are connected to the opposite ends of the said lever, respectively, and lead to the opposite ends of the car,where they terminate in chains adapted to be wound upon ordinary brake-spindles 4o operated by hand. In connection with this well-known arrangement I provide means for operating the same lever A by an electricallycontrolled drum arranged to have a greater or less magnetic or frictional engagement 5 with a rotating axle of the car. From one end of the lever A, I extend a chain A to a drum B, which normally surrounds loosely one of the car-axles C not engaged by a drivin g-motor. I provide two clutch-disks D and magnetic or frictional engagement between the said disks and-the drum, which will tend to rotate the drum as the axle turns and .wind up the brake-chain A to produce a pull upon the brake-lever A and an application of the brake. The drum B is normally engaged and held against rotation by a frictional lock applied through a spring, as will be hereinafter described; but an unlockingmagnet E, Figs. 1, 2, and 5, is-fixed so as to act in opposition to the spring when energized, and so unlock the drum to permit its rotation by the axle and then lock it again when it is deenergized after a sufficient pressure of the brake has been reached.

In Fig. 2 I have showna diagram of the electrical connections. At each end of the car a controller will be placed, which is rep resented in the diagram by the switches S and S, the former serving to admit the linev current from the wire 1, connected to the trolley, to the main brake-magnet F through a greater or less amount of the regulating resistance R, which in the last position is entirely removed from the circuit, while the latter serves to admit the line-current at will through the unlocking-magnet E. Both of these magnets are in shunt with the motors, being connected on one side to the trolley-' wire 1 through the switches aforesaid and on the other side to the ground by the wire 2.

In the present application I do not intend to claim any particular form of controller, and the two switches S and S are simply shown to indicate its general character.

. Turning to Fig. 3, the aforesaid drum,disks, and lock are shown in detail. Disks D and D are normally retracted by springs G, which are anchored to rings H, fixed on the axle, so as to turn therewith together with the disks. The drum B has at its two ends enlarged flanges B and B which contain the main energizing-coils, as shown in Fig. 4. The chain A Fig. 1, is to be wound up in the groove formed between flange B and a smaller iiange B while a locking flange B (see also Figs. 4 and 5) is placed between the flanges B and B and upon this lockingiiange the spring-actuated brake-shoes are applied. I

Turning to Fig. 4, which shows a section of the drum F and F are the two portions of the main coil F, contained, respectively, within the flanges 15 and 13 These coils are wound concentrically with the drum in grooves formed in the faces of the corresponding flanges, so as to make the central portion of each flange of one magnetic polarity and the peripheral portion of the opposite polarity, while the magnetic circuit is closed by the brake-disks. The two coils F and are in series, one terminal being the ring a, which is set on the inner face of the flange B but substantially insulated therefrom, and the other terminal being connected to the metal of the framework at c and thence to ground. A brush or block b is attached to the framework of the locking mechanism, which is stationary with the truck and bears upon the ring a, so as to maintain the electrical connection. The brush 1) is contained in a pocket on the framework adjacent to one point of the ring a, while the inner face of the flange B bears tightly against the said framework, and a leather washer (1 serves to maintain a water-tight joint between them, so as to fully protect the ring a and the brush 1), bearing thereon. K K are brass bushings which separate the drum B from the shaft 0 and form bearings on which the drum may turn. L is a loop in the chaingroove, to which the chain is attached.

Referring to Fig. 5, a framework J is provided for the locking mechanism and is supported at one end on springs M M, which bear upon across-beam O of the truck. The frame is also provided with downwardly-projecting legs J and J (see also Fig. 4,) which straddie the locking-flange B and surround the drum B. The frame thus rides upon the drum, but is prevented from turning therewith by its spring connection with the beam 0 of the truck. On the under side of the frame J are hung brake-shoes B and B by links L and L These shoes embrace the disk B, which has a beveled edge (see also Fig. 4) fitting into V-grooves in the shoes. The brake-shoes are normally held against the disk by an expansion-spring T, which draws on the upper end of the lever Q which is jointed to the brake-shoe 13 and connected by links Q to the opposite lever Q, jointed to the brake-shoe E is the unlockingmagnet, made as a solenoid, with its core E extended by a brass rod E to connect with the rod E which passes through the spring T and is jointed to the lever Q. When the magnet E is energized, it tends to draw its core E in toward the right against the force of the spring T, which by its expansion tends to force the core out and at the same time to draw up and apply'the shoes.

In operation the driver will energize the magnet F more or less strongly by moving the switch S, having previously moved the switch S to energize the magnet E and release the drum. Having thus secured the desired dedegree of magnetic attraction or friction between the drum B and the disks D D, the chain A will be wound up to give the desired pressure of the brakes, and the switch S will then be opened. The drum will thus be locked, so as to hold the brake, and the switch S may be opened and the brakes left applied. To release them, it is only necessary to close switch S, and then, if desired, a greater pressure may be attained by a more extended movement of the switch S.

It will be observed that my arrangement applies the chain and also the lock to the winding-drum at a point intermediate between the magnetic clutching devices on either end of the drum which cause the rotative engagement of the drum with the axle, so that the strain is balanced or exerted equally, or nearly so, upon both clutches.

What I claim as new, and desire to secure by Letters Patent, is-

1. The combination with the brakes of a vehicle, of a winding-drum therefor having an intermediate groove, a chain extending from the brakes and arranged to be wound in the said groove and flanges on either end of the drum containing the energizing-coils of magnetic clutches for engaging the drum with the said shaft.

2. The combination with the brakes of a ve= hicle, of a winding-drum therefor mounted on a driven shaft, energizing-coils contained in grooves on opposite ends of the drum, concentric therewith and armatures fastened to the said shaft so as to rotate therewith.

3. The combination with the brakes of a vehicle, of a winding-drum therefor mounted upon a driven shaft, flanges upon opposite ends of the said drum, energizing-coils concentric with the drum and placed in grooves within the said flanges and armatnres adjacent to the opposite ends of the said drum respectively and connected to the shaft so as to rotate therewith.

4. The combination with the brakes of a vehicle, of a winding-drum therefor, mounted upon a driven shaft, magnetic clutching devices for engaging the drum with the shaft, locking devices for the said drum mounted upon the vehicle, a spring for actuating the said locking devices and a magnet mounted upon the vehicle for releasing the said looking devices.

5. The combination with the brakes of a vehicle, of a winding-drum therefor mounted on a driven shaft, magnetic clutching devices at opposite ends of the said drum for engaging it with the driven shaft and looking devices for the drum applied thereto at an intermediate point between the said clutching devices.

6. The combination with the brakes of avehicle, of a winding-drum therefor mounted on a driven shaft, magnetic clutching devices for engaging the said drum with the shaft, a supporting-frame bearing upon the said drum but connected to the vehicle so as to be held against rotation, locking devices carried by the said frame and adapted to be applied to the drum, a spring for applying the said locking devices and a magnet for releasing them,- both mounted upon the said frame.

7. The combination with the brakes of a vehicle, of a Winding-drum therefor mounted upon a driven shaft, a frame having bearing on the said shaft, but held against rotation by a connection to the vehicle, brake-shoes depending from the said frame and engaging the said drum, a spring acting upon. the said brake-shoes through intermediate connections and a releasing-magnet acting in opposition to the said spring.

8. The combination with the brakes of a vehicle, of a winding-drum therefor mounted on a driven shaft, abrake-disk upon the said drum, a frame having bearings upon the drum on opposite sides of the said brake-disk, but connected to the vehicle so as to be held against rotation, brake-shoes carried by the said frame and a spring and a magnet also carried by the said frame, the former serving to apply and the latter to release the brakeshoes of the drum.

9. The combination with the brakes of a vehicle, of a winding-drum therefor mounted upon a driven shaft, locking devices for the said drum and a supporting-frame therefor bearing upon the said drum and having a yielding connection with the vehicle.

10. The combination with the brakes of a vehicle, of a Windingdrum therefor mounted on a driven shaft, clutching devices for engaging the drum with the shaft, a frame bearing at one side upon the said drum and at the other side upon springs connected to a cross-bar on the vehicle-truck, locking devices upon said frame adapted to hold the drum against rotation, and a spring and magnet also mounted on the said frame, the former serving to apply and the latter to release the said locking devices. 4

11. The combination with the brakes of a vehicle, of a winding-drum therefor mounted on a driven shaft, magnetic clutching devices on each end of the shaft forengaging the drum with the shaft, the said drum being provided with a groove between the clutching devices to receive the chain leading to the brakes, and a locking device for the drum also applied thereto between the said clutching devices.

12. The combination with the brakes of a vehicle, of a winding-drum therefor mounted upon a driven shaft, flanges on opposite ends of the said drum, energizing-coils in the said flanges, a circuit containing the said coils extending from one line-terminal to the other of the supply-circuit and including a regu-, =lator, armatures connected with the driven shaft and a locking device bearing upon the said drum, but held against rotation and operated by a spring in one direction and in the other direction by a magnet in a circuit parallel to the circuit aforesaid containing the energizing-coil of the clutching device.

13. The combination with the brakes of a on a driven shaft, an energizing-coil mounted upon the said drum and electrical contact devices between one terminal of the said coil and a fixed part of the vehicle contained within a Water-tight recess upon said drum.

14. The combination with the brakes of a vehicle, of a Winding-drum therefor mounted upon a driven shaft and provided with a vehicle,- of a Winding-drum therefor mounted I groove to receive the chain leading to the brakes, an energizing coil upon one side of said groove and upon the other side of said groove a sliding electrical contact connecting one terminal of the said coil with a circuitterminal upon a fixed part of the structure.

15. The combination with the brakes of a vehicle of a grooved winding-drum therefor, a rotating electromagnet located on one side of the groove for clutching said drum to a driving-shaft, an insulated ring on the other side of said groove forming a terminal of said magnet and contained in a recess closed bya relatively-moving part and a contact-piece on said part bearing-on the said ring.

16. The combination with the brakes of a vehicle of a winding-drum therefor, a rotating electromagnet for clutching said drum to a driving-shaft, an insulated ring forming a terminal of said magnet and set in a recess closed by a relatively moving part and a contactpiece on said part bearing against the said ring.

17. The combination with the brakes of a vehicle ofa winding-drum therefor, a rotating electromagnet for clutching said drum to a driving shaft and sliding contact devices contained in a closed recess between relativelymoving parts for connecting said magnet with the external current.

In Witness whereof I have hereunto set my hand, before two subscribing witnesses, this 22d day of November, 1900.

PERLEY P. CRAFTS. Witnesses:

F. O. MILDRAM, F. X. FITZPATRIGK.

IIO 

